The present invention relates to an improved tank assembly which is normally used in a laboratory location. The tank assembly receives aquatic life such as fish. The tank assemblies are used in, for example toxicity studies, biological studies and carcinogenic studies.
Because of the delicate nature of the studies, there must be no contamination resulting from the tank assembly itself. This has presented a problem in prior art structures. For example, in a longitudinally extending unit as shown in FIGS. 6, 7 and 8 of the enclosed drawings, expansion perpendicular to the longitudinal axis of the straight runs must be limited. One prior art method of limiting side expansion in tanks was the use of metallic tie rods. However, it has been found that tie rods are not satisfactory in this type of tank, because of corrosion and other contamination problems. The present assignee has made and sold tanks more than one year prior to the date of this application which have configurations similar to those shown in the enclosed drawings, but which did not include a reinforcing member in the upper flange, similar to that shown in FIG. 3 of the present application drawings. It has been found that the present tank assembly, which includes the novel reinforcement, provides a structure which eliminates the need for intermediate tie rods and, therefore, may be used in scientific studies of aquatic life.
Another way of attempting to solve the lateral deflection problem of tanks is disclosed in U.S. Pat. No. 4,244,486. This patent discloses U-shaped strut members and exterior angle members along the upper edge of the tank.
It is the object of this invention to provide a tank assembly having improved lateral stability.